WPB-26489 backend adminless scheduled jobs model and teardown support

[battermann]

Checklist

• Add a new entry in an appropriate subdirectory of changelog.d
• Read and follow the PR guidelines

[Copilot]

Pull request overview

This PR introduces an Arbiter-backed scheduled-jobs subsystem across services, migrating the meetings-cleanup worker to run via Arbiter and adding initial “adminless” reminder/deletion scheduled jobs, along with an internal /i/jobs UI/API mount in Brig.

Changes:

• Add Wire.API.Jobs, Wire.JobSubsystem, and Wire.JobStore to model/schedule jobs and persist minimal app-level metadata in Postgres.
• Replace the standalone meetings cleanup cron thread with an Arbiter worker pool (scheduledJobs.pollInterval controls polling cadence).
• Expose Arbiter’s internal UI + REST API through Brig’s internal routes under /i/jobs and /i/jobs/api/v1.

Reviewed changes

Copilot reviewed 56 out of 57 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
services/galley/src/Galley/Env.hs	Add Galley env field for passing a connection string into the job subsystem.
services/galley/src/Galley/App.hs	Wire JobSubsystem + JobStore interpreters and derive a Postgres connection string for Arbiter usage.
services/galley/galley.cabal	Add arbiter-core dependency for Galley.
services/galley/default.nix	Add arbiter-core Nix dependency for Galley.
services/brig/src/Brig/Run.hs	Adjust internal API wiring to pass env into IAPI.servantSitemap.
services/brig/src/Brig/App.hs	Initialize embedded Arbiter server/UI application and store it in Brig env.
services/brig/src/Brig/API/Internal.hs	Mount internal /i/jobs Raw app into Brig internal routes.
services/brig/default.nix	Add Arbiter packages (arbiter-core, arbiter-servant, arbiter-servant-ui).
services/brig/brig.cabal	Add Arbiter packages to Brig build-depends.
services/background-worker/test/Test/Wire/Util.hs	Extend test env with arbiterConnStr placeholder.
services/background-worker/test/Test/Wire/BackendNotificationPusherSpec.hs	Extend test env with arbiterConnStr placeholder.
services/background-worker/src/Wire/MeetingsCleanupWorker.hs	Refactor to expose runCleanupOldMeetings instead of owning the cron thread; move metrics increment into cleanup routine.
services/background-worker/src/Wire/Effects.hs	Add JobSubsystem/JobStore effects + interpreters and extend migration handling.
services/background-worker/src/Wire/BackgroundWorker/ScheduledJobs.hs	New scheduled-jobs dispatcher/worker wiring for meetings cleanup + adminless jobs via Arbiter.
services/background-worker/src/Wire/BackgroundWorker/Options.hs	Add scheduledJobs config section (poll interval).
services/background-worker/src/Wire/BackgroundWorker/Env.hs	Add arbiterConnStr to runtime env, derived from Postgres settings.
services/background-worker/src/Wire/BackgroundWorker.hs	Start the unified scheduled-jobs worker instead of the old meetings-cleanup worker thread.
services/background-worker/src/Wire/AdminlessJobsWorker.hs	New adminless reminder/deletion job handlers + scheduled job cleanup in app-level store.
services/background-worker/default.nix	Add arbiter-core dependency for background-worker.
services/background-worker/background-worker.integration.yaml	Add integration config for scheduledJobs.pollInterval.
services/background-worker/background-worker.cabal	Expose new modules and add arbiter-core dependency.
postgres-schema.sql	Update schema snapshot to include scheduled jobs table and related DB objects.
nix/manual-overrides.nix	Add overrides/jailbreaks for Arbiter package set.
nix/haskell-pins.nix	Add Arbiter source pin and package mapping.
libs/wire-subsystems/wire-subsystems.cabal	Add Arbiter deps and expose new job subsystem/store modules; add cron dep.
libs/wire-subsystems/test/unit/Wire/ConversationSubsystem/InterpreterSpec.hs	Add a JobSubsystem mock interpreter for conversation subsystem unit tests.
libs/wire-subsystems/src/Wire/Options/Keys.hs	Fix ASN.1 imports to use crypton-asn1-* packages explicitly.
libs/wire-subsystems/src/Wire/JobSubsystem/Workers.hs	New Arbiter worker runner helpers (recurring + one-off) with explicit defaults.
libs/wire-subsystems/src/Wire/JobSubsystem/Interpreter.hs	New Polysemy interpreter to schedule jobs into Arbiter and start workers.
libs/wire-subsystems/src/Wire/JobSubsystem.hs	New Polysemy effect and configuration types for scheduling/starting jobs.
libs/wire-subsystems/src/Wire/JobStore/Postgres.hs	New Postgres-backed interpreter for persisting minimal scheduled job metadata.
libs/wire-subsystems/src/Wire/JobStore.hs	New Polysemy effect for scheduled job metadata persistence.
libs/wire-subsystems/src/Wire/ConversationSubsystem/Update.hs	Schedule adminless reminder/deletion jobs when last admin leaves; add reminder event emission.
libs/wire-subsystems/src/Wire/ConversationSubsystem/Interpreter.hs	Add internal actions for adminless deletion/reminder execution paths.
libs/wire-subsystems/src/Wire/ConversationSubsystem/Action.hs	Factor conversation deletion into reusable removeConversation.
libs/wire-subsystems/src/Wire/ConversationSubsystem.hs	Add new internal conversation actions for adminless job execution.
libs/wire-subsystems/postgres-migrations/20260624095944-extend-job-model.sql	Add scheduled_jobs table + indexes migration.
libs/wire-subsystems/default.nix	Add Arbiter and cron dependencies for wire-subsystems.
libs/wire-api/wire-api.cabal	Expose new Jobs API modules in wire-api.
libs/wire-api/test/unit/Test/Wire/API/Conversation.hs	Extend event tests for new ConvAdminlessReminder type classification.
libs/wire-api/src/Wire/API/Team/FeatureFlags.hs	Accept both legacy and current JSON keys for search visibility defaults.
libs/wire-api/src/Wire/API/Routes/Internal/Jobs.hs	New internal route type for mounting the embedded jobs app.
libs/wire-api/src/Wire/API/Routes/Internal/Brig.hs	Add Jobs app route into Brig internal API type.
libs/wire-api/src/Wire/API/Jobs.hs	New job payload types, queue names, and registry definition for Arbiter.
libs/wire-api/src/Wire/API/Event/Conversation.hs	Add ConvAdminlessReminder event type and corresponding event payload schema.
libs/types-common/src/Data/Id.hs	Introduce ScheduledJobId and ScheduledJob id tag.
libs/extended/src/Hasql/Pool/Extended.hs	Add shared postgresqlConnectionString helper and refactor pool init to use it.
integration/test/Test/AdminlessGroups.hs	Add integration coverage for adminless scheduling and Arbiter execution path.
integration/test/Notifications.hs	Add helper to detect adminless reminder notifications.
flake.nix	Add Arbiter git input.
flake.lock	Lock Arbiter input revision/hash.
docs/src/developer/reference/config-options.md	Document scheduledJobs.pollInterval.
charts/wire-server/values.yaml	Add Helm value for background-worker.config.scheduledJobs.pollInterval.
charts/wire-server/templates/background-worker/configmap.yaml	Render scheduledJobs config into background-worker configmap.
changelog.d/2-features/WPB-26489	Feature changelog entry for Arbiter-backed scheduled jobs + adminless jobs.
changelog.d/0-release-notes/WPB-26489	Release notes for Arbiter scheduling and /i/jobs endpoints.
cabal.project	Add source-repository-package entries for Arbiter packages.

[akshaymankar]

Haven't read everything, comments based on just trying to understand the arbiter stuff.